With the continuous advances in science and technology, more and more electronic devices, such as smart phones, tablet PCs, notebook computers and all-in-one computers, etc., have entered into and brought great convenience to people's lives. To meet various needs of customers, electronic devices are required to possess more features, which, consequently, results in growing power consumption for electronic devices. Electronic devices have growing demands for battery's discharge capacity; and, to protect each functional module of electronic devices, the control accuracy for battery's discharge overcurrent protection becomes increasingly important. However, the technical issue of low control accuracy of discharge overcurrent protection of a battery in the prior art cannot meet the safety requirements of powered devices.